Brussels sprouts and saffron risotto

Boil a pot of salted water and throw in brussels sprouts, blanching them whole. This may take 3-5 minutes depending on size. When ready, the point of a sharp knife should pierce the centre with just a little resistance. Drain and plunge them into a bowl of iced water for 5 minutes, then drain again. Slice each sprout lengthwise into 3-4 pieces and keep in a bowl. In a large, wide pan heat butter and oil, add onion and lightly fry until transparent - do not let it colour. Add rice and stir until grains become transparent. Deglaze with wine, allowing it to evaporate completely. Add boiling stock, then saffron, and simmer, stirring until liquid is almost entirely incorporated. Add stock a little at a time until risotto is almost cooked - 15-20 minutes depending on the rice. Add brussels sprouts and stir through. Remove from heat, season with salt and stir in remaining butter and grated parmesan. Rest for 3-4 minutes with lid on before serving.